1. Field of the Invention
The present invention relates to a steering device provided for steering a small watercraft that has a plurality of outboard motors which are independently controllable.
2. Description of the Related Art
Some small watercraft utilize an outboard motor that incorporates a propulsion device and that is attached to a rear end of a hull. The outboard motor pivots about a swivel axis to adjust a propulsive direction by a steering operation of an operator so that the hull moves in a desired direction.
Other small watercraft include a plurality of outboard motors which propulsive directions and propulsive forces are independently controllable. Such watercraft have, for example, a pair of outboard motors on a transom board, and the propulsive directions and the propulsive forces of the respective outboard motors are individually controlled. A resultant vector of the propulsive forces determines a moving direction of the hull. For example, the hull can move in the right transverse direction when it approaches or leaves from a pier or the like, or can make an immediate turn at the spot in accordance with the resultant vector.
Conventionally, in order to steer small watercrafts having such multiple outboard motors, an operating device such as a joystick or the like which differs from a steering unit that is used for usual steerage is applied. Such an operating device is disclosed in Japanese Patent Application Nos. JP02-227395A, JP2000-313398A, and U.S. Pat. No. 6,234,853.
However, in order to use the operating device such as the joystick or the like together with the steering unit, a particular space is required for accommodating the operating device. A control mechanism for the operating device is also required. Thus, a construction of the steering device can be complicated.
Further, the operator is compelled to use both of the steering unit and the joystick, and also is compelled to change hands under various steerage conditions. Thus, the steerage can be more for such small watercrafts which are primarily so designed that the steerage is easy for the purpose of leisure or the like. That is, the combination of the steering unit and the operating device is inconvenient for such small watercrafts.